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v3.20.1

Share Incentive Plan - Additional Information (Details) |  | 1 Months Ended | 12 Months Ended |  |  |
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Oct. 20, 2017 $ / shares shares | Oct. 20, 2017 $ / shares ¥ / shares shares | Apr. 26, 2019 CNY (¥) | Aug. 31, 2017 shares | Dec. 31, 2019 CNY (¥) | Dec. 31, 2018 CNY (¥) | Dec. 31, 2017 CNY (¥) shares | Aug. 24, 2018 shares | Oct. 31, 2017 shares | Oct. 20, 2017 ¥ / shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense | ¥ |  |  |  |  | ¥ 2,970,000 | ¥ 3,851,000 | ¥ 288,763,000 |  |  |
Dividend payout ratio assumed |  |  |  |  | 0.00% |  |  |  |  |
Unrecognized share-based compensation expenses | ¥ |  |  |  |  | ¥ 7,421,000 |  |  |  |  |
Weighted average recognition period of unrecognized share-based compensation expenses |  |  |  |  | 2 years 2 months 12 days |  |  |  |  |
Directors and Management |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Share based compensation expense | ¥ |  |  |  |  |  |  | ¥ 83,133,000 |  |  |
Additional Ordinary Share | Directors and Management |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Shares issued without consideration | shares |  |  |  | 146,930 |  |  |  |  |  |
Additional Ordinary Share | Independent Directors |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Shares issued in exchange for services | ¥ |  |  | ¥ 1,100,000 |  |  |  |  |  |  |
2017 Share Incentive Plan | Additional Ordinary Share |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Number of shares approved for grant | shares |  |  |  |  |  |  |  | 345,503 | 483,846 |
Common Stock, Capital Shares Reserved for Future Issuance | shares |  |  |  |  |  |  |  | 829,349 |  |
Scheme I |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Number of shares granted | shares | 363,452 | 363,452 |  |  |  |  |  |  |  |
Exercise price | (per share) | $ 0.0047 | $ 0.0047 |  |  |  |  |  |  |  | ¥ 0.0312
Number of shares exercised | shares |  |  |  |  |  |  | 363,452 |  |  |
Allocated Share-based Compensation Expense | ¥ |  |  |  |  |  |  | ¥ 205,630,000 |  |  |
Scheme II |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Number of shares granted | shares | 66,053 | 66,053 |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense | ¥ |  |  |  |  |  | ¥ 2,751,000 | ¥ 0 |  |  |
Exercise price | (per share) | $ 84.75 | $ 560.95 |  |  |  |  |  |  |  |
Scheme II | Vested on First Anniversary Grand Date |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Options vesting percentage |  |  |  |  | 10.00% |  |  |  |  |
Scheme II | Vested on Over Next Three Years |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Options vesting percentage |  |  |  |  | 20.00% |  |  |  |  |
Scheme II | Vested on Third Anniversary of Company IPO |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Options vesting percentage |  |  |  |  | 30.00% |  |  |  |  |
Scheme II | Vested on Fourth Anniversary of Company IPO |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Options vesting percentage |  |  |  |  | 40.00% |  |  |  |  |

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